ExtechRH390 Precision Dual Display Hygro Thermometer Psychrometer

Just what I needed

These are the humidity meters that we use for work. We don't use the measured dew point, instead we do our own calculations to determine it (I find that the measured dew point is off).This meter is very easy to use. Just make sure that you aren't holding the meter too close to your face (otherwise your breath will skew the results).

I just received the above product today. I have gone through the instructions on how to change from F to C which did work however it is already reading E2 error and needs to be recalibrated? According to the instructions this requires a salt reference bottle? Is this something that I now have to purchase? If so, we will likely return the unit. Please advise, thank you.

Appareil précis et facile à utiliser, lecture directe d'humidité relative et température. Portable peut être utilisé partout pour tout genre de vérification.Il faut cependant prendre quelques minutes pour que l'appareil se stabilise pour un résultat plus précis.Très bon rapport qualité-prix, je le recommande.

Needs to be calibrated for the humidity reading.The calibration bottle cost a bomb,much more than the device itself.DO NOT BUY.Amazon and the seller were kind enough to arrange for a promt refund.One should buy only the thermomter....